Screening for Skin Cancer in Adults: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force.

Abstract

Skin cancer, primarily melanoma, is a leading cause of morbidity and mortality in the United States. To provide an updated systematic review for the US Preventive Services Task Force regarding clinical skin cancer screening among adults. MEDLINE, PubMed, and the Cochrane Central Register of Controlled Trials were searched for relevant studies published from January 1, 1995, through June 1, 2015, with surveillance through February 16, 2016. English-language studies conducted in asymptomatic populations 15 years and older at general risk for skin cancer. Relevant data were abstracted, and study quality was rated. Melanoma incidence and mortality, harms from cancer screening, diagnostic accuracy, and stage distribution. No randomized clinical trials were identified. There was limited evidence on the association between skin cancer screening and mortality. A German ecologic study (n = 360,288) found a decrease of 0.8 per 100,000 melanoma deaths in a region with population-based skin cancer screening compared with no change or slight increases in comparison regions. The number of excisions needed to detect 1 skin cancer from clinical visual skin examinations varied by age and sex; for example, 22 for women 65 years or older compared with 41 for women aged 20 to 34 years. In 2 studies of performing visual skin examination, sensitivity to detect melanoma was 40.2% and specificity was 86.1% when conducted by primary care physicians (n = 16,383). Sensitivity was 49.0% and specificity was 97.6% when skin examinations were performed by dermatologists (n = 7436). In a case-control study of melanoma (n = 7586), cases diagnosed with thicker lesions (>0.75 mm) had an odds ratio of 0.86 (95% CI, 0.75-0.98) for receipt of a physician skin examination in the prior 3 years compared with controls. Eight cohort studies (n = 236,485) demonstrated a statistically significant relationship between the degree of disease involvement at diagnosis and melanoma mortality, regardless of the characterization of the stage or lesion thickness. Tumor thickness greater than 4.0 mm was associated with increased melanoma mortality compared with thinner lesions, and late stage at diagnosis was associated with increased all-cause mortality. Only limited evidence was identified for skin cancer screening, particularly regarding potential benefit of skin cancer screening on melanoma mortality. Future research on skin cancer screening should focus on evaluating the effectiveness of targeted screening in those considered to be at higher risk for skin cancer.